NCT Group 99M, 2000M manual Introduction

Fig. 1.2-5

1 Introduction

Reference Point

The reference point is a fixed point on the machine-tool. After power-on of the machine, the slides have to be moved to the reference point. Afterwards the control system will be able to interpret data of absolute coordinates as well.

Coordinate System

The dimensions indicated in the part drawing are measured from a given point of the part. That point is the origin of the workpiece coordinate system. Those dimensional data have to be written at the coordinate address in the part program. E.g., X340 means a point of coordinate 340 mm in the coordinate system of the workpiece.

Fig. 1.2-4

The coordinate system

specified in the control

system and in which the control interprets the

positions, is different from the coordinate system of

the workpiece. For the control system to make a

correct workpiece, the zero points of the two coordinate systems have

to be set at the same position. This can be achieved, e.g., by moving the tool center to a point

of known position of the part and setting the coordinate system of the control to that value.

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